Based on information from RVO, the Darwin VAAC reported that Balbi erupted on 7 May. Ash was not detected on satellite imagery. [Correction: RVO later confirmed that Balbi did not erupt on 7 May and attributed the reports to thunderstorm activity.]

Aerial inspection was carried out on 22 August, after the 16 August, M 7.8 earthquake that struck 100 km to the W. The inspection revealed profuse white vapor coming from large-output fumaroles in the main fumarole field of the stratovolcano's summit amphitheater. In contrast, emissions at Crater B were moderate and from diffused sources.

Recent landslides were noted in two of the summit craters. The more extensive slides were on the W wall of Crater B. These landslides were thought to have been caused by shaking during the 16 August earthquake.

In general, the visible activity at Balbi appeared to be similar to that observed during previous inspections in the late 1980's. However, emissions may have been more voluminous in 1995.

Balbi marks the highest point on Bougainville Island, forming a summit composed of coalesced cones and lava domes and hosting a large solfatera field. Interviews with local inhabitants suggested that Balbi's last eruption took the lives of a number of people in about 1800-1850.

Information Contacts:Patrice de Saint-Ours and Ben Talai, RVO.

Weekly Reports - Index

Based on information from RVO, the Darwin VAAC reported that Balbi erupted on 7 May. Ash was not detected on satellite imagery. [Correction: RVO later confirmed that Balbi did not erupt on 7 May and attributed the reports to thunderstorm activity.]

Information is preliminary and subject to change. All times are local (unless otherwise noted)

Balbi, Bougainville's highest point, is in the N-central part of the island on the axial volcanic chain. In [what is possibly an eroded caldera at the summit of the composite cone, seven craters] lie on a N-S ridge about 3 km long. [There are also two cones about 2 km W of the line of craters.] Only Crater B, about 600 m in diameter and second from the S, shows activity. Anthropological evidence suggests an explosive eruption accompanied by nuées ardentes and fatalities, sometime between 1800 and 1850 [but recent geological work does not support this.]

"A boiling mud pool and up to a dozen large, very active fumaroles flanked the lineament of craters. Large collapses have occured into Crater B, and further extensive tension cracks were visible around the crater's rim. Many small solfataras were still active in the W wall of Crater B. The lake in Crater C had diminished in size." [Recent RVO investigations show that the fumaroles are aligned orthogonally to the 7-crater lineament and that the mud pool is no longer active.]

"A brief aerial inspection of Balbi was made on the 27th. No changes were noted. Voluminous white emissions continued from the 1-km-long fumarole field in the NE part of the summit amphitheatre, and from sources in one of the summit craters (Crater B)."

Aerial inspection was carried out on 22 August, after the 16 August, M 7.8 earthquake that struck 100 km to the W. The inspection revealed profuse white vapor coming from large-output fumaroles in the main fumarole field of the stratovolcano's summit amphitheater. In contrast, emissions at Crater B were moderate and from diffused sources.

Recent landslides were noted in two of the summit craters. The more extensive slides were on the W wall of Crater B. These landslides were thought to have been caused by shaking during the 16 August earthquake.

In general, the visible activity at Balbi appeared to be similar to that observed during previous inspections in the late 1980's. However, emissions may have been more voluminous in 1995.

Balbi marks the highest point on Bougainville Island, forming a summit composed of coalesced cones and lava domes and hosting a large solfatera field. Interviews with local inhabitants suggested that Balbi's last eruption took the lives of a number of people in about 1800-1850.

Information Contacts:Patrice de Saint-Ours and Ben Talai, RVO.

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Synonyms

Tutue

Basic Data

Volcano Number

Last Known Eruption

Elevation

LatitudeLongitude

255010

Unknown - Evidence Credible

2715 m / 8907 ft

5.92°S
154.98°E

Volcano Types

Stratovolcano Lava dome(s) Pyroclastic cone(s)

Rock Types

MajorAndesite / Basaltic Andesite

Tectonic Setting

Subduction zoneCrustal thickness unknown

Population

Within 5 kmWithin 10 kmWithin 30 kmWithin 100 km

314
505
11,904
127,928

Geological Summary

The large Balbi stratovolcano forms the highest point on Bougainville Island. The summit of the complex andesitic volcano is part of a large number of coalesced cones and lava domes. Five well-preserved craters occupy a NW-SE-trending ridge north of the summit cone, which also contains a crater. Three large valleys with steep headwalls dissect the flanks. The age of the most recent eruption is not known precisely. An oral tradition of a major eruption during the 19th century is now thought to be in error, but could refer to minor eruptive activity from this relatively youthful-looking volcano. Fumaroles are located within 600-m-wide Crater B and on its W flank.

References

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography.

Eruptive History

Deformation History

There is no Deformation History data available for Balbi.

Emission History

There is no Emissions History data available for Balbi.

Photo Gallery

The broad, complex Mount Balbi stratovolcano is seen here in profile from the village of Wakunai, east of the volcano along the NE coast of Bougainville Island. Balbi, the highest and largest-volume volcano on the island, has an elongated profile resulting from the formation of a NW-SE-trending chain of volcanic vents. The age of the most recent eruption of Balbi volcano is not known precisely. An oral tradition of a major eruption during the 19th century is now thought to be in error, but could refer to minor eruptive activity.

Photo by Wally Johnson, 1987 (Australia Bureau of Mineral Resources).

The massive Balbi stratovolcano forms the highest point on Bougainville Island. The 2715-m summit of the complex volcano is part of a large number of coalesced cones and lava domes. Five well-preserved craters occupy a NW-SE-trending ridge north of the summit of the volcano, which also contains a crater. Crater C, containing a small lake, is seen here from the east. Steam from a fumarole field on the western flank of 600-m-wide Crater B is visible at the left. The latest eruption of Balbi may have been as recent as the mid-19th century.

Photo by Wally Johnson, 1987 (Australia Bureau of Mineral Resources).

Much of the left side of this NASA image with north to the upper left is covered by volcanic products from Tore volcano in the Emperor Range on NW Bougainville Island. The Tore massif lies to the left of the light-colored area at the center of the image, Balbi volcano. Two Pleistocene ignimbrites from Tore formed a broad fan that extends the coastline to the west (lower left). The dark-colored caldera lake of Billy Mitchell volcano is at the right, above an ash plume originating from Bagana volcano.

GVP Map Holdings

The maps shown below have been scanned from the GVP map archives and include the volcano on this page. Clicking on the small images will load the full 300 dpi map. Very small-scale maps (such as world maps) are not included. The maps database originated over 30 years ago, but was only recently updated and connected to our main database. We welcome users to tell us if they see incorrect information or other problems with the maps; please use the Contact GVP link at the bottom of the page to send us email.

Smithsonian Sample Collections Database

Affiliated Sites

The DECADE portal, still in the developmental stage, serves as an example of the proposed interoperability between The Smithsonian Institution's Global Volcanism Program, the MAGA Database, and the EarthChem Geochemical Portal. The Deep Earth Carbon Degassing (DECADE) initiative seeks to use new and established technologies to determine accurate global fluxes of volcanic CO2 to the atmosphere, but installing CO2 monitoring networks on 20 of the world's 150 most actively degassing volcanoes. The group uses related laboratory-based studies (direct gas sampling and analysis, melt inclusions) to provide new data for direct degassing of deep earth carbon to the atmosphere.

WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.

Middle InfraRed Observation of Volcanic Activity (MIROVA) is a near real time volcanic hot-spot detection system based on the analysis of MODIS (Moderate Resolution Imaging Spectroradiometer) data. In particular, MIROVA uses the Middle InfraRed Radiation (MIR), measured over target volcanoes, in order to detect, locate and measure the heat radiation sourced from volcanic activity.

Using infrared satellite Moderate Resolution Imaging Spectroradiometer (MODIS) data, scientists at the Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, developed an automated system called MODVOLC to map thermal hot-spots in near real time. For each MODIS image, the algorithm automatically scans each 1 km pixel within it to check for high-temperature hot-spots. When one is found the date, time, location, and intensity are recorded. MODIS looks at every square km of the Earth every 48 hours, once during the day and once during the night, and the presence of two MODIS sensors in space allows at least four hot-spot observations every two days. Each day updated global maps are compiled to display the locations of all hot spots detected in the previous 24 hours. There is a drop-down list with volcano names which allow users to 'zoom-in' and examine the distribution of hot-spots at a variety of spatial scales.

EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).